Mr Walden was best known for an interview with Margaret Thatcher in October 1989, which helped precipitate her downfall.
He was the Labour MP for Birmingham Ladywood from 1964 until 1977, where he was a renowned orator, before joining ITV, where he is remembered for his “exhaustive but courteous” technique.
Mr Walden succumbed to complications arising from emphysema on the afternoon of Thursday 9 May, at his home in St Peter Port, Guernsey.
He leaves a widow, Hazel Walden, and four sons.
Mrs Walden said she was “happily married” for 43 years and her late husband was “very cheerful, always happy and got on well with people”.
She said: “The biggest regret that he would have is that he didn’t live to see Brexit, because he was a passionate Brexiteer. Margaret Thatcher would never have let things get as far as Theresa May has.
“He agreed with Nigel Farage that the only way is out, unless we wish to give up our British rights and tradition to be held in a superstate.
“To be dominated by a capricious and undemocratic Brussels-Berlin axis is not something he would have wanted.”
His friend John Wakefield, who worked with Mr Walden at ITV as his producer and editor, said they had “a terrific time”.
“Brian was an immensely lively and entertaining person to work with,” he said.
“He was very much a team guy who loved what everybody had to say, including the most lowly, recent researcher, and was hugely gregarious and fun. He was brilliant because he was such a fantastic public speaker and, as a former politician, he knew how they operated – he was able to read their minds.”
Mr Wakefield praised his colleague’s “formidable, almost photographic” knowledge of history, with a focus on the “heroic” as well as around the American civil war and the French Revolution.
He said his friend had never been very interested in the “London dinner party scene”, preferring smaller groups of friends, and moved to Guernsey for the “old-fashioned lifestyle”.
And he explained Mr Walden’s shift from Labour towards the Thatcherite right wing was “consistent” and derived from his “very, very poor” childhood.
“He regarded two things as the enemy of the respectable working class,” said Mr Wakefield, “the complacent squire-archy Tories who spent too much time in the golf club and on the other hand the Marxist left, who didn’t understand capitalism.”